Method for reducing the pressure drop associated with a fluid subjected to a turbulent flow

Abstract

Method for reducing the pressure drop associated with a fluid subjected to a turbulent flow which comprises introducing at least one latex into said fluid, comprising: (a) a continuous aqueous phase; (b) a plurality of particles, dispersed in said continuous aqueous phase, of at least one branched (co) polymer having a branching degree {GR) ranging from 0.05 to 0.6, preferably from 0.08 to 0.5, and a weight average molecular weight (M w ) of the parent (co) polymer ranging from 100,000 Daltons to 700,000 Daltons, preferably ranging from 140,000 Daltons to 350,000 Daltons. Said method can be advantageously used in the case of a pressure drop in pipelines transporting liquid hydrocarbons such as, for example, petroleum, crude oils and refinery or petrochemical products, in particular for long distances.

1 . A method for reducing the pressure drop associated with a fluid subjected to a turbulent flow which comprises introducing at least one latex into said fluid, comprising:
 a) a continuous aqueous phase;   b) a plurality of particles, dispersed in said continuous aqueous phase, of at least one branched (co)polymer having a branching degree (GR) ranging from 0.05 to 0.6 and a weight average molecular weight (M w ) of the parent (co)polymer ranging from 100,000 Daltons to 700,000 Daltons.   
     
     
         2 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1 , wherein said branched (co)polymer has a branching degree (GR) ranging from 0.08 to 0.5. 
     
     
         3 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1 , wherein said branched (co)polymer has a weight average molecular weight (M w ) of the parent (co)polymer ranging from 140,000 Daltons to 350,000 Daltons. 
     
     
         4 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1 , wherein said fluid is selected from petroleum crude oils, stabilized petroleum, and other liquid hydrocarbons. 
     
     
         5 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1 , wherein said continuous aqueous phase comprises at least one antifreeze fluid selected from: ethylene glycol, propylene glycol, glycerine, ethyl ether, diglyme, polyglycols, and glycol ethers. 
     
     
         6 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 5 , wherein said antifreeze fluid is ethylene glycol. 
     
     
         7 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 5 , wherein said antifreeze fluid is present in said continuous aqueous phase in a such a quantity as to have a concentration of said antifreeze fluid in the latex ranging from 2% by weight to 20% by weight with respect to the total weight of said latex. 
     
     
         8 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1 , wherein said latex has a viscosity, measured at 15° C. and at 300 s −1  ranging from 30 mPa·s to 100 mPa·s. 
     
     
         9 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1 , wherein said latex has a content of particles of branched (co)polymer, determined by means of the standard ISO 124:2011, ranging from 30% by weight to 70% by weight with respect to the total weight of the latex. 
     
     
         10 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1 , wherein said particles of branched (co)polymer have an average diameter ranging from 50 nm to 600 nm. 
     
     
         11 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1 , wherein said branched (co)polymer comprises at least one oil in a quantity ranging from 0 phr to 50 phr. 
     
     
         12 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 11 , wherein said oil is selected from oils having a flash point, measured according to the standard ASTM D93-12, higher than 65° C., and a glass transition temperature (Tg) lower than −40° C. 
     
     
         13 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1 , wherein said latex is present in said fluid in a quantity ranging from 0.1 ppmw to 500 ppmw. 
     
     
         14 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1  any of the previous claims, wherein said branched (co)polymer is a styrene-butadiene copolymer. 
     
     
         15 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 14 , wherein said styrene-butadiene copolymer has a content of bound styrene ranging from 15% by weight to 40% by weight, with respect to the total weight of the copolymer. 
     
     
         16 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 1 , wherein said latex is prepared by the emulsion (co)polymerization of monomers selected from: styrene, 1,3-butadiene, optionally in the presence of other unsaturated mono- and di-ethylene monomers, in a quantity lower than or equal to 10% by weight with respect to the total weight of the monomers present in the reaction mixture; α-β-unsaturated acids having the following formulae CH 2 ═C(R)—COOH wherein R═H, a C 1 -C 4  alkyl group or CH 2 COOH; acrylamide; vinyl acetate; isoprene; 2,3-dichloro-1-3 butadiene; 1-chloro-1,3-butadiene; vinyl chloride; C 1 -C 4  alkylacrylate groups; C 1 -C 4  alkylmethacrylate groups; divinylbenzene; vinylpyridine, N-methyl-N-vinylacetamide; N-vinyl-caprolactam; N,N-isopropylacrylamide. 
     
     
         17 . The method for reducing the pressure drop associated with a fluid subjected to a turbulent flow according to  claim 16 , wherein at the end of said (co)polymerization, the latex obtained is subjected to a concentration phase and, optionally, to an agglomeration phase and to a final concentration phase.